I NEED LAN CARD DRIVER FOR D600 LAPTOP

If you want the driver for your Dell laptop, the best place to get it is at support.dell.com.You need to input the model you have, ( which I believe to be a Latitude D600), and choose drivers.
On the driver page, choose your computer's language, network for category and all for importance.
This brings up about 20+ possible downloads.
You then need to find the ones that apply to the network card in your computer that are labeled as drivers.
Anything labeled as firmware is optional and will upgrade the operation of your card if applied. Utilities are also optional and are usually used to change operational settings of the card.
There will be only one driver for your card that you have to download, everything else is optional.
Once you have the driver, look at the device manager in WinXP.
If the network card [ethernet adapter] is not showing there, then there should be an unknown device. 
Right click on the unknown device and choose update drivers and point the update wizard to the driver you downloaded.
That should solve the problem.